Magnetic feed roll system



Jan. 11, 1966 A. FOWLER MAGNETIC FEED ROLL SYSTEM 2 Sheets-Sheet 1 Filed July 24 1962 2 F f cl C I INVENTOR AZEA64/VOA'A FdA/AEA Jan. 11, 1966 A. FOWLER 3,228,680

MAGNETIC FEED ROLL SYSTEM Filed July 24, 1962 2 Sheets-Sheet z a /Z6 70 a; 64 62 /24 /Z4 /Z0 INVENTOR 4447/1/05? FdA ZEK BY 2 Z drraPn/EYJ United States Patent 3,228,680 MAGNETIC FEED ROLL SYSTEM Alexander Fowler, 334 Westover Road, Stamford, Conn. Filed July 24, 1962, Ser. No. 211,984 4 Claims. (Cl. 27151) This invention relates to feed rolls for feeding sheet material, and more particularly to magnetic feed rolls.

Magnetic feed rolls are well known and have many advantages when working with ferrous sheet material. However, they have not proved satisfactory for the feed of ferrous sheet metal which is very thin, or for the feed of nonferrous sheet materials.

The general object of the present invention is to overcome this disadvantage, and to provide an improved magnetic feed roll system which is well adapted to the handling of thin ferromagnetic sheet metal, and also nonferrous sheet materials.

To accomplish the foregoing general object, and other more specific objects which will hereinafter appear, my invention resides in the magnetic feed roll elements and their relation one to another, as are hereinafter more particularly described in the following specification. The specification is accompanied by drawings in which:

FIG. 1 is a fragmentary perspective view showing the use of a fixed magnet coil which avoids the need for slip rings;

FIG. 2 is an elevation showing part of a feed roll system embodying features of the invention;

FIG. 3 is a section taken approximately in the plane of the line 3--3 of FIG. 2;

FIG. 4 is an elevation showing another form of the invention;

FIGS. 5, 6 and 7 are schematic views showing successive stages in the passage of a sheet through a feed roll system which is energized only when a sheet is being fed;

FIG. 8 is a perspective view of part of a feed roll system like that shown schematically in FIGS. 5, 6 and 7; and

FIG. 9 is a wiring diagram showing the feed roll supply circuitry.

Referring to the drawing, and more particularly to FIGS. 2 and 3, the feed roll system comprises a magnetic feed roll 12, 14 located on one side of, in this case below, the feed path. It further comprises a ferromagnetic pinch roll 16 on the other side, in this case above, the feed path. The pinch roll 16 serves to complete the magnetic circuit of the feed roll 12, 14.

The feed and pinch rolls preferably are so mounted as to be relatively movable toward or away from one another. Usually the feed roll is mounted in fixed bearings, one of which is shown at 18, while the pinch roll is movable. In the present case the pinch roll 16 is carried between upright guides 20. Additional means may be provided to normally raise the pinch roll 16 when the feed roll is deenergized. In the present case there are support rods or bolts 22 (only one being shown in the drawing) which are vertically slidable in bearings 24 and which are raised by compression springs 26, it being understood that the mechanism shown in FIGS. 2 and 3 is duplicated at the other end of the rolls. The rise caused by the compression spring is limited by a nut 28, winch may be appropriately adjusted at the lower end of rod 22. Collars 30 may be secured at the outer ends of the pinch roll 16 to limit its axial movement.

The feed roll comprises spaced ferromagnetic discs 12 and 14 secured on a ferromagnetic shaft 32. An electromagnet coil 34 is located between the discs 12 and 14. A supply circuit for the coil may be established through appropriate slip rings and brushes, as shown in my Patented Jan. 11, 1966 Patent 2,650,824 issued September 1, 1953, and entitled Feeding of Magnetic Sheet Material. However, in the present case a fixed coil is employed, thereby eliminating the need for slip rings.

Referring to FIG. 1, as well as FIGS. 2 and 3, the magnet coil 34- is protected by a nonferrous housing made up of end discs 36, an outer shell 38, and an inner sleeve 40. The shaft 32 is freely rotatable within the sleeve 40.

Wiring for energizing the coil 34 may be carried through appropriate pipe or conduit 42, having a fitting 44, and a nipple 46, leading to the housing 38. The feed discs 12 and 14 are secured on the ferromagnetic shaft 32 by suitable means, here shown simply as set screws 48 (FIG. 2). It will also be understood that there may be a series of such feed units, that is, pairs of discs with a coil between the discs of each pair, depending on the width of the sheet material to be fed. In a typical feed system there may be, say six such units, that is, twelve feed discs and six magnet coils, all on a single feed shaft. It is for that reason that electric conductors are shown at both ends of pipe 42, so that the supply circuit may be carried to all of the magnet coils.

The pipe 42 is itself supported by a suitable bracket 59 which is secured to a support rail or frame member 52. This rail also carries the main bearing 18, and the block 24 for the pinch roll guides. These parts are all duplicated at the other end.

The bearing block 18 is preferably nonmagnetic. With heavy ferrous sheet material the magnetic circuit is through shaft 32 to disc 12 to the sheet metal resting on discs 12 and 14, and thence through disc 14 and shaft 32. However, with the present arrangement the magnetic circuit is completed through the ferromagnetic pinch roll 16, instead of (or in addition to) the flux path provided by the sheet metal. The pinch roll is drawn toward the feed roll, with the sheet material therebetween, and the material is, therefore, effectively fed, even though it may be very thin material. Indeed, it may be a nonferrous metal, or nonmetallic material such as sheet fiber.

The advantage of the open-topped guides 20, 20 shown in FIG. 3 is that the pinch roll 16 may be bodily removed by simply lifting it out of position when not needed. The pinch roll may be removed when feeding ferrous sheet metal of adequate gauge, and is restored when feeding nonferrous material, say sheet aluminum or fiber, or even ferrous material when very thin.

The pinch roll may be differently mounted, and may be normally raised by different means. Thus in FIG. 4 the pinch roll 69 is carried on arms 62 pivoted at 64, thereby affording movement of the pinch roll toward or away from the magnetic feed roll 66. The pinch roll is normally raised by means of a counterweight 68, and the lift of the pinch roll may be limited by a suitable stop 70. As before, the pinch roll 60 is made of ferromagnetic material, and the feed roll 66 comprises magnetized discs. These are preferably intermittently energized by electromagnet coils, and the latter may be either rotatable, or nonrotatable as shown in FIGS. 1-3.

In FIG. 4 the feed system is associated with a mechanical shear 120, the flywheel of which is indicated at 122. The sheet material is supported on a series of idle rollers 124 in horizontal alignment with the feed roll 66. A feeler and microswitch are indicated at 126. The feed roll 66 is driven by means not shown in the drawing, typically a gear motor, that is, an electric motor with built-in reduction gearing, much as described later in connection with FIG. 8.

The pinch roll may be below instead of above the feed roll, and such an arrangement is illustrated in FIG. 8, in which the ferromagnetic pinch roll 72 is located The shaft 80 is preferably ferromagnetic, and may be carried in nonmagnetic bearing blocks, one of which is shown at 82. The feed roll is motor driven, in this case by means of an electric motor 84 with builtin reduction gearing, terminating in a sprocket wheel or pulley 86 driving a chain or belt 88 leading to a sprocket wheel or pulley 90 on the shaft 80. It will be understood that the feed rolls shown in all figures of the drawing are driven by suitable motor means, even though the motor may not be shown in the drawing.

The .pinch roll 72 is carried in bearings 92 having vertical bearing slots 94 which afford vertical movement of the pinch roll. In this case the separation is obtained gravitationally when the magnetic roll is deenergized. When the magnetic roll is energized the pinch roll is drawn upward to the magnetic roll, and serves to complete the magnetic circuit as previously described.

The motor preferably operates continuously, but the feed roll preferably is energized only when a sheet is being fed. For this purpose a control switch is preferably disposed in the path of the sheet material. This is schematically illustrated in FIGS. 5, 6 and 7 of the drawing. In FIG. a microswitch 96 is controlled by a feeler 100. This is in its down position, thereby opening the circuit to the magnetic feed roll 76. The pinch roll 72 is therefore in its down position. A sheet 102 is approaching the feeler 100 and the feed rolls, and on contacting the feeler raises it to the position shown in FIG. 6, thereby changing the microswitch 96 and energizing the feed roll 76, at which time the pinch roll 72 is raised as shown in FIG. 6, in which the sheet 102 is being fed by the feed rolls. In FIG. 7 the sheet 102 has passed through the feed rolls, at which time the feeler 100 has again dropped, thereby opening the microswitch 96 and deenergizing the feed roll 76, so that the pinch roll 72 has again dropped.

The circuit is shown in somewhat simplified'form in FIG. 9, in which closing of main switch 104 starts the motor 84 which drives the magnetic feed roll. The latter is preferably energized by direct current, and with an AC. circuit on lines L1 and L-2, as here assumed, a full Wave rectifier may be employed, typically a selenium rectifier bridge, shown at 106. The rectifier output is connected to the electromagnet coil 34 my means of conductors 108, 110 and 112, the switch 96 being located in this circuit. A fixed capacitor 114 may be provided to minimize arcing at the switch contacts. In practice the microswitch may control a relay which in turn controls the power to the magnet coil, but for simplicity the switch 96 is here shown directly in the power supply circuit.

The feed rolls may be associated with other apparatus such as a press or a saw, as well as a shear as shown in FIG. 4, or any other fabricating equipment where positive controlled conveying of a sheet is required.

It is believed that the construction and operation of my improved magnetic feed roll system, as well as the advantages thereof, will be apparent from the foregoing detailed description. It will also be apparent that while I have shown and described the invention in several forms, changes may be made Without departing from the scope of the .invention, as sought to be defined in the following claims.

1 claim:

1. A feed roll system for feeding large sheets of sheet metal along a desired feed path having a series of rollers on which the sheets rest, said system comprising a magnetic feed roll on one side of the feed path, a ferromagnetic pinch roll on the other side of the feed path, means mounting both rolls for rotation, motor means to drive one of the rolls, said rolls being so mounted as. to be relatively movable toward or away from one another to pinch a sheet directly therebetween, said pinch. ro l serving to complete the magnetic circuit of the feed roll when feeding thin or non-ferrous sheet metal, said feed roll comprising two spaced ferromagnetic discs secured on a ferromagnetic shaft with an electromagnet coil between said discs, said electromagnet coil being housed in a nonmagnetic and nonrotatable housing positioned around the ferromagnetic shaft, and being energized through fixed wiring, thereby eliminating the need for slip rings.

2. A feed roll system for feeding large sheets of sheet metal along a desired feed path having a series of rollers on which the sheets rest, said system comprising a magnetic feed roll on one side of the feed path, a ferromagnetic pinch roll on the other side of the feed path, means mounting both rolls for rotation, motor means to drive one of the rolls, said rolls being so mounted as to be relatively movable toward or away from one another to pinch a sheet directly therebetween, said pinch roll serving to complete the magnetic circuit of the feed roll when feeding thin or non-ferrous sheet metal, said feed roll comprising, two spaced ferromagnetic discs secured on a ferromagnetic shaft with an electromagnet coil between said discs, said electromagnet coil being housed in a nonmagnetic and nonrotatable housing positioned around the ferromagnetic shaft, and being energized through fixed wiring, thereby eliminating the need for slip rings, a supply circuit for said coil, and a switch in said circuit operated by a feeler engaging and controlled by the passage of a sheet through the feed rolls for energizing said coil when a sheet is being fed, and for deenergizing said coil in the intervals between the sheets.

3. A feed rollsystern for feeding large sheets of sheet metal along a desired feed path having a series of rollers on which the sheets rest, said system comprising a magnetic feed roll on one side of the feed path, bearing blocks for said feed roll, a ferromagnetic pinch roll on the other side of the feed path, means mounting said pinch roll for rotation, motor means to drive one of the rolls, said rolls being so mounted as to be relatively movably toward or away from one another to pinch a sheet directly therebetween, said pinch roll serving to complete the magnetic circuit of the feed roll when feeding thin or non-ferrous sheet metal, said feed roll comprising two spaced ferromagnetic discs secured on a ferromagnetic shaft with an electromagnet coil between said discs, said electromagnet coil being housed in a nonmagnet and nonrotatable housing positioned around the ferromagnetic shaft, and being energized through fixed wiring, thereby eliminating the need for slip rings, and the aforesaid bearing blocks of the ferromagnetic shaft of the feed roll being nonmagnetic.

4. A feed roll system for feeding large sheets of sheet metal along a desired feed path having a series of rollers on which the sheets rest, said system comprising a magnetic feed roll on one side of the feed path, bearing blocks for said feed roll, a ferromagnetic pinch roll on the other side of the feed path, means mounting said pinch roll for rotation, motor means to drive one of the rolls, said rolls being so mounted as to be relatively movable toward or away from one another to pinch a sheet directly therebetween, said pinch roll serving to complete the magnetic circuit of the feed roll when: feeding thin or non-ferrous sheet metal, said feed roll comprising two spaced ferromagnetic discs secured on a fer-romagnetic shaft with an electromagnet coil between said discs, said electromagnet coil being housed in a nonmagnetic and nonrotatable housing positioned around the ferromagnetic shaft, and being energized through fixed wiring, thereby eliminating the need for slip rings, a supply circuit for said coil, and a switch in said circuit operated by a feeler engaging and controlled by the passage of a sheet through the feed rolls for energizing said coil when a sheet is being fed, and for de-energizing said coil in the intervals between the sheets, the afore-.

5 said bearing blocks of the ferromagnetic shaft of the feed r011 being nonmagnetic.

References Cited by the Examiner UNITED STATES PATENTS 421,776 2/1890 Sprague et a1. 271-51 835,903 11/1906 Grant 27151 1,848,856 3/1932 Wagner et a1. 27174.1 2,827,291 3/1958 Wilson et a1. 271-45 6 2,880,997 4/1959 Brown 271-45 2,990,092 6/1961 Begun et a1. 226176 FOREIGN PATENTS 716,229 9/1954 Great Britain. 750,760 6/ 1956 Great Britain.

ROBERT B. REEVES, Primary Examiner.

ROBERT A. LEIGHEY, Examiner. 

1. A FEED ROLL SYSTEM FOR FEEDING LARGE SHEETS OF SHEET METAL ALONG A DESIRED FEED PATH HAVING A SERIES OF ROLLERS ON WHICH THE STREETS REST, SAID SYSTEM COMPRISING A MAGNETIC FED ROLL ON ONE SIDE OF THE FEED PATH, A FERROMAGNETIC PINCH ROLL ON THE OTHER SIDE OF THE FEED PATH, MEANS MOUNTING BOTH ROLLS FOR ROTATION, MOTOR MEANS TO DRIVE ONE OF THE ROLLS, SAID ROLLS BEING SO MOUNTED AS TO BE RELATIVELY MOVABLE TOWARD OR AWAY FROM ONE ANOTHER TO PINCH A SHEET DIRECTLY THEREBETWEEN, SAID PINCH ROLL SERVING TO COMPLETE THE MAGNETIC CIRCUIT OF THE FEED ROLL WHEN FEEDING THIN OR NON-FERROUS SHEET METAL, SAID FEED ROLL COMPRISING TWO SPACED FERROMAGNETIC DISCS SECURED ON A FERROMAGNETIC SHAFT WITH AN ELECTROMAGNETIC COIL BETWEEN SAID DISCS, SAID ELECTROMAGNETIC COIL BEING HOUSED IN A NONMAGNETIC AND NONROTATABLE HOUSING POSITIONED AROUND THE FERROMAGNETIC SHAFT, AND BEING ENERGIZED THROUGH FIXED WIRING, THEREBY ELIMINATING THE NEED FOR SLIP RINGS. 